Journal of fish biology最新文献

{"title":"Body size of male Atlantic salmon (Salmo salar L.) at introduction of a 5-week LD12:12 winter signal influences their decision to mature early or smoltify.","authors":"Enrique Pino-Martinez, Kristine F Staveland, Mitchell S Fleming, Pablo Balseiro, Cindy Pedrosa, Sigurd O Handeland","doi":"10.1111/jfb.70068","DOIUrl":"https://doi.org/10.1111/jfb.70068","url":null,"abstract":"<p><p>Sexual maturation of male Atlantic salmon post-smolts ('jacking') is undesired in aquaculture and seems to occur due to the intensification in modern facilities. Maturation depends on internal and external factors (temperature, photoperiod, feed availability, energy levels, body size, genetic background) that act on the brain-pituitary-gonad axis to trigger maturation. This study assessed the influence that the body weight at the time of the photoperiod manipulation performed to induce smoltification can have on early maturation or smoltification. For that, 900 parr (41.3 ± 3.7 g) were assigned to four size-photoperiod treatments: constant light (LL), a winter signal (5-week LD12:12) starting when fish was 70.0 ± 8.4 g (70WS), a similar winter signal at 114 ± 9.9 g (110WS) and at 182.9 ± 35.7 g (180WS). The trial took place in fresh water, except for the last 2 weeks in each treatment carried out in full seawater. Body weight and condition, gonadosomatic index and proportion of maturing males, gill Na⁺, K⁺, ATPase activity and blood parameters (chloride and sodium, cortisol, glucose and cholesterol) were measured to assess progression of smoltification or maturation. In addition, pituitary messenger RNA (mRNA) transcription of tshβb (a paralog of the thyrotropin thyroid-stimulating hormone) was analysed to investigate its potential role in the regulation of any of the two processes. Results evidenced that body size of male salmon was relevant for the developmental response to a winter signal, be it maturation or smoltification. An early winter signal (70WS and 110WS) induced clearer signs of smoltification (reduced condition factor, high energy mobilization and little stress response in seawater among others) and no tendency to mature early. In contrast, a late or no winter signal (180WS and LL) induced a strong stress response in seawater, poor morphological signs of smolting and energy mobilization, and a higher tendency to mature early. It was difficult to directly relate pituitary tshβb transcription with both smoltification or maturation, because this gene seemed to act primarily as a timekeeper displaying large upregulations in response to increases in daylength (irrespective of size) but no changes under constant light. These results evidence that an increase in daylength when salmon is large enough to have developed sufficiently or accrued energy resources may pose high risk that a proportion of them prioritize sexual maturation over smoltification. Producers may take this into consideration when optimizing protocols for post-smolt production.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143969614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prematuration differences in male and female Atlantic cod: Investigating sex ratio, length and ecotype disparities in juveniles.","authors":"Sander Vollmerhaus Digre, Per Erik Jorde, Arild Folkvord, Jakob Hemmer-Hansen, Halvor Knutsen","doi":"10.1111/jfb.70070","DOIUrl":"https://doi.org/10.1111/jfb.70070","url":null,"abstract":"<p><p>Sexual size dimorphism (SSD) and skewed sex ratios are common in the animal kingdom, and marine fishes, such as the Atlantic cod (Gadus morhua), are no exception. This study utilized newly discovered sex-linked genetic markers to investigate young-of-the-year cod in the Skagerrak system, comprising approximately 2700 individuals from North Sea and fjord ecotypes. Overall, no significant difference in sex ratio was observed overall (51% females, 49% males), with consistent findings across 14 locations and three sheltering degrees. Although slightly more females were found in exposed areas, and slightly more males in sheltered regions, these differences were not significant. Size variation between female and male cod was generally negligible. These results indicate a likely purely genetic sex determination system in Atlantic cod and a lack of prematuration growth differences between sexes. This research enhances our understanding of the Atlantic cod, providing more insight into the Atlantic cod population in the Skagerrak and emphasizing the importance of genetic factors in sex determination.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144021685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the type locality of the Naso Stardrum Stellifer naso (Jordan 1889), and comments on morphological change over a century.","authors":"Jonas Andrade-Santos, Marcelo R Britto","doi":"10.1111/jfb.70072","DOIUrl":"https://doi.org/10.1111/jfb.70072","url":null,"abstract":"<p><p>Stellifer naso is known from the State of Bahia (Brazil), but there is a lack of an accurate definition of its type locality. Thayer's expedition (around 1865-1866), led by Louis Agassiz and staff from the Museum of Comparative Zoology (MCZ, Harvard University), intended to explore Brazilian fauna and flora, with most of its material housed in the MCZ and used to describe several species, including S. naso. Examination of specimens from the original description of that species, housed in the MCZ and the Smithsonian National Museum of Natural History, helped review the accurate point of origin for such specimens. A combination of data from reproductive biology and the history of the region further support the actual type locality of S. naso as Iguape Bay, with an error radius of 2.5 km. Damming in the Paraguaçu River in the early 1980s might have had an impact on the morphological variation over time recorded to this species.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144023379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Movement behaviours of stocked and wild lake trout Salvelinus namaycush determined using acoustic telemetry.","authors":"Matthew H Futia, J Ellen Marsden","doi":"10.1111/jfb.70071","DOIUrl":"https://doi.org/10.1111/jfb.70071","url":null,"abstract":"<p><p>Hatchery practices are a critical tool of fisheries management to supplement diminished fish populations and restore extirpated species. However, stocking programs that successfully restore self-sustaining populations are rare. Unintentional artificial selection and domestication of hatchery-reared fish are potential limitations to the success of stocked individuals by selecting for behaviours that are poorly suited for natural conditions. Here, we compared seasonal movement behaviours between an established population of hatchery origin (stocked) and naturally produced (wild) lake trout (Salvelinus namaycush) in Lake Champlain at a range of sizes, including immature and mature fish. Fifty-six stocked and 34 wild lake trout were implanted with acoustic transmitters, including 45 transmitters with temperature and pressure (depth) sensors, to evaluate three-dimensional movement. Movement behaviours were assessed based on the number of distinct lake regions used, proportional time spent among lake regions, average daily distance travelled and depth distribution. Overall, horizontal and vertical movements were similar between stocked and wild lake trout across sizes, although individuals tended to occupy shallower depths at larger sizes. Seasonal differences in movement behaviours were observed and in some cases were dependent on origin. For all lake trout, average daily movement was greatest during fall and least during summer. Depth occupied, however, had an opposite trend, with the deepest average depths during summer and shallowest during fall and winter. The proportion of time spent among lake regions and variability in depth occupied also varied seasonally but only for wild fish, and included less time spent in individual regions and greater depth variability during fall compared to other seasons. While origin had insignificant effects in most models we evaluated, model predictions consistently suggested stocked lake trout had slightly smaller movements than wild fish. These results suggest that hatchery practices may have long-term, unintended effects on fish behaviour yet overall differences are likely subtle.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144010861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Not all social coral reef fishes form strict size-based dominance hierarchies: An investigation of intraspecific size ratios in Dascyllus aruanus.","authors":"Rebecca Branconi, Peter M Buston, Marian Y L Wong","doi":"10.1111/jfb.70047","DOIUrl":"https://doi.org/10.1111/jfb.70047","url":null,"abstract":"<p><p>We present a random pattern of body size ratios between adjacent ranked group members in the humbug damselfish Dascyllus aruanus. This random distribution of size ratios differs from the other well-known group-living coral reef fishes which exhibit non-random, well-defined and closely regulated size differences between ranks. Our results suggest a relaxation of social constraints in D. aruanus which may be due to its social system, mating system, capacity for movement or a combination thereof. Investigating how these traits co-vary within and among populations is an interesting avenue of future research.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144023376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The grime fighting potential of fish guts and the battle for responsible consumption","authors":"William Bernard Perry","doi":"10.1111/jfb.16075","DOIUrl":"https://doi.org/10.1111/jfb.16075","url":null,"abstract":"&lt;p&gt;We live in a world that is dominated by mixed capitalist economies, a continuum of market and government control (Jahan &amp; Mahmud, &lt;span&gt;2022&lt;/span&gt;). Yet, at the heart of any capitalist system is the dependency on consumption to drive economic growth, which is problematic when resources are finite and integral to ecosystems. Consumption also generates waste. Escalating consumption observed throughout the 20&lt;sup&gt;th&lt;/sup&gt; Century can be found at the root of many environmental catastrophes. Aquatic systems and fish are on that front line, suffering from consumption (e.g. overfishing (Barausse &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2011&lt;/span&gt;), deforestation (Bojsen &amp; Barriga, &lt;span&gt;2002&lt;/span&gt;) and over abstraction of water (Benejam &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2010&lt;/span&gt;)) and the end products of consumption (e.g. climate change (Kutsyn, &lt;span&gt;2025&lt;/span&gt;), plastic pollution (Rochman &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2013&lt;/span&gt;), soil pollution (Stauffer &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2011&lt;/span&gt;), air pollution (Nduka &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2022&lt;/span&gt;) and water pollution (Carney Almroth &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2021&lt;/span&gt;).&lt;/p&gt;&lt;p&gt;To try and save natural systems from the ravages of overconsumption and to protect the natural world in which capitalist systems depend, the United Nations created Sustainable Development Goal 12: Responsible consumption and production (UN, &lt;span&gt;2024&lt;/span&gt;). To achieve the targets within this goal, a post-capitalism vision and roadmap has been proposed by some, whereby the tenets of neoliberalism (free-market capitalism, deregulation, and reduction in government) are replaced with sustainable consumption and reduced waste (Dermody &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2021&lt;/span&gt;). One approach to reducing waste is through the idea of a circular economy, where materials never become waste.&lt;/p&gt;&lt;p&gt;However, turning waste materials into useful products that can re-enter society takes innovation and can be susceptible to greenwashing. One industry guilty of producing vast quantities of waste are food fisheries, which are geared towards harvesting fillets for human consumption, leaving up to 70% of the fish behind as a by-product (e.g. heads, viscera, skin, bones and scales) (FAO, &lt;span&gt;2022&lt;/span&gt;). At best, that 70% will end up in fishmeal for aquaculture, but more often will end up in landfill, open-air dumps or water sources. This is despite these tissues containing valuable nutrients, minerals, and, as explored by Friedman &lt;i&gt;et al&lt;/i&gt;. (&lt;span&gt;2025&lt;/span&gt;), enzymes - specifically proteinases found in the intestine.&lt;/p&gt;&lt;p&gt;Proteinases are the most widely used enzymes in industrial bioprocesses, and in previous work Friedman &lt;i&gt;et al&lt;/i&gt;. (&lt;span&gt;2022&lt;/span&gt;) characterized the optimal pH and temperature for these proteinases, isolated from the guts of four fish species. However, for these enzymes to be used in products such as detergents they must be able to function in the presence of other compounds such as surfactants and oxidizing agents. In this issue, Friedman &lt;i&gt;et al&lt;/i&gt;","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":"106 4","pages":"989"},"PeriodicalIF":1.7,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jfb.16075","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143884052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reproductive behaviour, developmental morphology and sexual dimorphism in Taranetz's lumpsucker, Eumicrotremus taranetzi (Cottoidei: Cyclopteridae) - A long-term aquarium study.","authors":"Koji Matsuzaki, Toshiaki Mori, Yoshiaki Kai","doi":"10.1111/jfb.70034","DOIUrl":"https://doi.org/10.1111/jfb.70034","url":null,"abstract":"<p><p>Spawning behaviour, ontogenetic development and sexual dimorphism of the Taranetz's lumpsucker Eumicrotremus taranetzi are described based on aquarium observations. Reproductive behaviour was observed from ca. 1000 days after hatching [dah, female ca. 45.0 mm body length (BL), male ca. 37.0 mm BL], including territorial males remaining on the artificial substrate after spawning and protecting eggs until hatching. Some of the eggs were moved to a smaller tank for hatching. Eggs hatched approximately 110 days after spawning at an average water temperature of 2.8°C. Pelvic-fin sucker formation begins in the egg at 83 days (completed at 90 days) after fertilization (daf). Newly hatched larvae have a smooth body (without spines or bony tubercles), fully developed fins (except for the caudal fin) and adhesive suckers. Larvae attach themselves to the bottom or side of the tank immediately after hatching. Bony tubercles on the body appear first on the head at 50 dah. Males and females exhibited distinct sexual dimorphism in 15 body measurements and the number of bony tubercles at 200 days post hatching (dph), probably related to the egg-guarding behaviour of males.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144004777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Freshwater fishes of the Waterberg aquatic ecoregion, South Africa: Diversity, taxonomic conflicts and conservation concerns.","authors":"Darragh J Woodford, Mandla Magoro, Wilbert T Kadye, Martinus Scheepers, Yonela Sithole, Tadiwa I Mutizwa, Tholoana Ntokoane, Albert Chakona","doi":"10.1111/jfb.70007","DOIUrl":"https://doi.org/10.1111/jfb.70007","url":null,"abstract":"<p><p>Southern Africa is a region denoted by both high levels of fish diversity, some of it cryptic and unrecognised by current taxonomy, and severely threatened freshwater ecosystems. The Waterberg, a key aquatic ecoregion of the greater Limpopo River basin in South Africa, represents an area with high terrestrial conservation value but is lacking in aquatic biodiversity information. This study characterised this unique aquatic ecoregion's fish diversity, their biogeographic patterns and threats to this biodiversity. A total of 29 fish species (11 families, 19 genera) were identified, with many distinct upland fish communities occurring within the high-altitude headwaters of the ecoregion, whereas lowland fish communities tended to be more homogeneous. Mitochondrial CO1 barcoding revealed genetically distinct lineages in four presumed-widespread southern African species: the shortfin barb, Enteromius brevipinnis (Jubb, 1966); hyphen barb, Enteromius bifrenatus (Fowler, 1935); straightfin barb, Enteromius paludinosus (Peters, 1852) and snake catfish, Clarias theodorae Weber, 1897, that were restricted to the Waterberg aquatic ecoregion. The level of genetic divergence suggests that these four Waterberg-restricted lineages are likely new candidate species. These findings indicate the Waterberg to be a biogeographic island within the greater Zambezian ichthyofaunal region of southern Africa, which should be prioritised for aquatic ecosystem conservation. Current terrestrial conservation structures in the region, encapsulated within the Waterberg Biosphere Reserve, appear to protect this distinct ichthyofauna from human land-use-derived impacts. Nonetheless, the presence of the invasive predatory largemouth bass (Micropterus nigricans) inside the biosphere represents a credible conservation threat. Engagement with biosphere stakeholders will be critical for managing this threat to the Waterberg's unique ichthyofauna going forward.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144063864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advances in telemetry approaches and technologies applied to fish ecology and management","authors":"Johann Mourier,&nbsp;Taryn S. Murray,&nbsp;Robert J. Lennox,&nbsp;Kim Birnie-Gauvin","doi":"10.1111/jfb.70064","DOIUrl":"10.1111/jfb.70064","url":null,"abstract":"&lt;p&gt;Telemetry and biologging have been key tools in fish ecology for several decades (Hussey et al., &lt;span&gt;2015&lt;/span&gt;; Matley et al., &lt;span&gt;2022&lt;/span&gt;; Watanabe &amp; Papastamatiou, &lt;span&gt;2023&lt;/span&gt;) and helped uncover several mysteries within this realm, including migrations, behaviour, activity and space use, intra- and interspecific interactions or human impacts. The technology has remarkably improved since its first application, allowing us to monitor smaller-sized fish for longer periods. Sensors on board tags add additional capacity to measure internal and external properties of the tagged fish, such as their temperature, depth and acceleration. In addition, the analytical tools and approaches to infer fish movement and behaviour derived from telemetry data have considerably advanced to allow complex and high-dimensional spatial and temporal analyses.&lt;/p&gt;&lt;p&gt;There is a global community of fish-tracking scientists who use animal tracking tools to address applied and fundamental questions about fish populations in every ocean of the world and scores of inland waters. The Sixth International Conference on Fish Telemetry gathered many of these scientists in Sète, France, from 11 to 16 June 2023, providing the opportunity to share the latest advances in telemetry approaches and technologies for studying movement ecology of fish and for fisheries management. The present collection of papers is representative of the current trends in fish ecology studied through the prism of biologging and telemetry, with 11 (41%) papers focused on marine systems, 7 (26%) on freshwater systems and 9 (33%) addressing both systems (i.e., estuary or transitions between rivers and sea).&lt;/p&gt;&lt;p&gt;This special issue offers readers a wide range of approaches and tagging methods applied to dive deeper into a fish's movement ecology. Although the more common tagging methods provided new insights into fish ecology with acoustic telemetry determining the large-scale migrations of rays in a regional network of receivers (Elston et al., &lt;span&gt;2025&lt;/span&gt;) and pop-up archival satellite tags providing the first long-term migration route of sunfish (&lt;i&gt;Mola mola&lt;/i&gt; L.) in the Mediterranean Sea (Rouyer et al., &lt;span&gt;2025a&lt;/span&gt;), other developing tools were also applied. For example, data-storage tags were used in combination with acoustic telemetry to study connectivity of pollack (&lt;i&gt;Pollachius pollachius&lt;/i&gt;) in the French-English Channel (Gonse et al., &lt;span&gt;2025&lt;/span&gt;). In addition, several approaches were proposed to study predation in fish, including acoustic tags with acceleration sensors to map the dynamics of shark activity and its associated predation pressure on prey (Laurioux et al., &lt;span&gt;2025&lt;/span&gt;) or the test and use of predation tags in several case studies: brown trout (&lt;i&gt;Salmo trutta&lt;/i&gt; L.; Kennedy et al., &lt;span&gt;2025&lt;/span&gt;), largemouth bass (&lt;i&gt;Micropterus nigricans&lt;/i&gt;; Shorgan et al., &lt;span&gt;2025&lt;/span&gt;) and salmon (&lt;i&gt;Salmo salar&lt;/i&gt;; Waters et al., &lt;spa","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":"106 5","pages":"1257-1259"},"PeriodicalIF":1.7,"publicationDate":"2025-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/jfb.70064","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144063828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hidden in plain view: A new Labeo (Cyprinidae: Labeoninae) endemic to the Kouilou-Niari River basin in the Lower Guinea ichthyological province.","authors":"Tobit L D Liyandja, Melanie L J Stiassny","doi":"10.1111/jfb.70062","DOIUrl":"https://doi.org/10.1111/jfb.70062","url":null,"abstract":"<p><p>Labeo niariensis sp. nov., a small-sized Labeo species, is described from the Kouilou-Niari River system in the Lower Guinean ichthyofaunal province. The species is a member of the newly erected Labeo annectens species group. Morphologically, it is distinguished from all congeners by the presence of a deeply bifurcate posterior process of the kinethmoid. It further differs from all the described Lower Guinean Labeo, except L. annectens and Labeo nunensis, by possessing six (vs. five or fewer) pre-dorsal vertebrae. The new species is further distinguished from L. annectens and L. nunensis by the presence of a prominent anterior notch and moderately developed posterior process on the first infraorbital (lachrymal) versus absence of an anterior notch and an elongated posterior process, presence of a deeply ovoid second infraorbital versus narrow and elongate, and by meristic and morphometric differences in body shape and proportions. L. niariensis is currently only known from the Kouilou-Niari River system in the Republic of Congo.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144027092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}